1. Technical Field
The present invention relates to drivers, electro-optical apparatuses, electronic devices, or the like.
2. Related Art
A driver that drives a display panel needs various types of voltages such as a power supply of a source drive amplifier, a power supply of a gate drive amplifier, a power supply of a gradation voltage generation circuit, and a common voltage of the display panel, and therefore includes a power supply circuit for generating these necessary voltages. For example, JP-A-2007-212897 and JP-A-2010-145738 disclose a power supply circuit having a plurality of voltage boosting circuits (primary voltage boosting circuit to quaternary voltage boosting circuit), and a driver that includes a source driver and a gate driver which operate while receiving power supplies generated by a voltage boosting operation of the voltage boosting circuits in the power supply circuit.
Some kinds of driver use a source driver of a type that samples and holds a driving voltage. For example, JP-A-2009-118457 discloses a source driver that has a D/A conversion circuit and a plurality of amplifier circuits, which sequentially sample and hold a gradation voltage that is output in a time division manner from the D/A conversion circuit, and drive source lines of the display panel based on the held gradation voltage.
The voltage boosting circuits included in the power supply circuit in the driver monitor a boosted voltage and repeat stop and resumption of the voltage boosting operation in order to maintain this boosted voltage at a substantially constant level. When resuming the voltage boosting operation, the resumption of the voltage boosting operation causes a ground voltage, a substrate voltage, or the like to fluctuate, for example, and the noise caused thereby is propagated to circuits or the like in the driver.
In the case of using a sample-hold source driver such as the one disclosed in JP-A-2009-118457, there is a possibility that the voltage (sampling voltage) held by the source driver has an error due to the aforementioned noise from the voltage boosting circuits. Since the driving voltage for driving pixels is determined by the voltage held by the source driver, a write voltage of the pixels becomes inaccurate.